I wouldn't say that the ISS has been a whole and complete waste. Sure - it is years behind schedule, etc., etc. but one has to admit that it has taught us a lot in terms of international cooperation, waste management, construction in zero-G among a long list of others. I truly believe that the next step to maintaining a presence in space has to come in the way of building a lunar base. It will be challenging but will have huge advantages, not the least of which is a base which is permanent (won't have to be de-orbited after a number of years), a base capable of providing on-site labs to do all sorts of analysis on lunar soil, rocks, regolith and basically, a base which will extend our knowledge of our own natural satellite by many orders of magnitude. And who knows? Perhaps one day we'll be advanced enough to manufacture components from materials found on the moon and be using that very base to send heavy spacecraft to other heavenly bodies like Mars. Discuss.